Psyker
This weapon Blocks both Melee and Ranged attacks. Additionally, Block Cost is reduced by 22.5-30%.
Enemy gains 1-4 Stacks of Soulblaze on Critical Hit.
3-6 Bleed Stacks on Critical Hit.
6-12% Critical Chance for each Enemy Hit by your previous attack. Stacks 5 times.
This is my favourite build
It goes for synergies with souldblaze and Crit chance.
You're pretty immortal with Scier's Gaze up and as long as enemies are around you. With Mettle, By Crack of Bone and Souldrinker you have ridiculous toughness regeneration, while dragging out Scrier's Gaze for it's full duration.
Kinetik Flayer often takes care of elites in your Soulblaze horde on it's own thanks to the DOT, which of course spreads more Soulblaze around.
The fire Shotgun can Crit reliably with Scattershot as the alternate fire mode has infinite cleave. With all Scattershot stacks your Critchance is between 70 and 95 depending on Souldrinker and Scrier's Gaze. It also gives you 5% Toughness for every Crit, so shooting a horde can refill your Toughness in one hit.
Much more than Soulblaze, fire seems to trigger Kinetik Flayer more reliably, so with fire and bleed from the Shotgun you can one tap specials and elites from a surprising distance most of the time. Hitting a group of elites, spreading fire and bleed, triggering Kinetic Flayer and adding Soulblaze to the rest as well feels pretty nice. The Trifecta of DOTs is also pretty effective into bosses, Hit some Warp slashes, trigger Scrier's Gaze and get close with the shotgun for more stacks.
The Greatsword's Warp slash and Shotgun alt. fire headshots can stagger anything beneath a boss reliably and they help you take care of Crushers, Maulers and Maniacs. The Greatsword shove can also topple Maulers but be aware of its Peril generation if you're in Scrier's gaze and maxed out.
Last but not least we have Brainburst with Empowered Psionics, this helps start up Soulblaze with Perilous Combustion, increases the power of Kinetic Flayer and helps deal with far off gunners.
If you're not a shotgun fan here are two alternatives:
The Boltpistol with Puncture can take care of distant threats, elites and Maulers while also being able to proc Kinetic Flayer, if less reliable. It also has a neat synergy with the Warp slash where you need to switch to the Pistol immediately after a slash: This procs the Bleed from Puncture on all enemies hit by your Warp slash.
Voidstrike Staff is also good alternative for the shotgun, skip Psychic Leeching and Charged Up to get to True Aim for more reliable Crits and then take the blessings to double shoot and spread Soulblaze on Crits. This is a lot more Peril intensive though and I found the Shotogun to be more reliable in high Peril moments for DMG output , or for Maniacs/Elites in Hordes